First Drive: 2019 Chevrolet Silverado 2.7T Four-Cylinder
Down with Displacement: For most buyers, the Silverado’s new 2.7-liter is all they’ll need
There's a reason the 2.7-liter, turbocharged inline four-cylinder in the 2019 Chevrolet Silverado drives like a diesel. Kevin Luchansky, the assistant chief engineer behind the engine's clean-sheet design, says his team was focused on building a truck powerplant from the start, and that meant delivering as much torque as possible right off of idle.
"Most turbos have been really focused on developing high horsepower per liter," Luchansky says. "We weren't chasing that. We were chasing low, low-speed torque. No one's doing that with a gas engine."
The new four-cylinder makes 348 lb-ft of torque from the word go, from 1,500 to 4,000 rpm. By comparison, GM's 5.3-liter V-8 manages just 35 more lb-ft, and takes until 4,100 rpm to achieve it. Those are hard numbers to get your head around, and they're only possible because Luchansky and his team borrowed some tricks from heavy-duty turbodiesel design.
In a traditional turbo, exhaust gasses flow down a common channel before being split by a divider cast into the turbo housing, then move on to the turbine. The problem is that the design allows for some energy to escape, which means less boost at low rpm when there are fewer exhaust pulses. The 2.7-liter's turbo is different, using two separate, larger passages that each run to one half of the turbine. The "dual volute" design maximizes energy from each pulse, resulting in more power at lower rpm. The technology isn't new, as BorgWarner has used the principal on some commercial diesel engines in the past, but this is the first time it's shown up on a small-displacement gasoline engine.
"You end up with a better pressure ratio and aerodynamic efficiency across the turbine at low speeds," Luchansky says. "At high speeds it's not as efficient."
Even so, the engine is good for 310 horsepower at 5,600 rpm. GM threw everything it knows about modern powertrain design at the 2.7-liter for the 2019 Chevy Silverado, including variable valve timing and lift, with two different hydraulically actuated cam profiles. The system also allows for cylinder deactivation, a first for the company's four cylinder engines. Under specific conditions, cylinders two and three drop out to conserve fuel. Engineers chose one and four to power the truck in deactivation mode because the integrated exhaust manifold design means that the cooling system pulls slightly more heat from the outer cylinders, allowing the 2.7 to operate in deactivation mode for longer periods of time than would otherwise be possible.
There's other cleverness packed into the engine's cooling system, too. Using an electric water pump as part of the Active Thermal Management system, the 2.7 can independently control cylinder head, block, and transmission cooling to reduce warm up time and to improve fuel economy. An electronically controlled valve can open and close, directing coolant accordingly during extreme temperature situations.
Luchansky and his team even turned their eyes to the lubrication system. The oil pump is a variable pressure unit that can tailor oil flow to both engine speed and load—all in the pursuit of greater power and efficiency.
Add it all up, and it's not hyperbole to call the direct-injection, 2.7-liter, turbocharged engine a wonder, maybe the most technologically advanced powerplant from General Motors in a decade. The fact that it's a four-cylinder isn't surprising. That it's debuting in the full-size Silverado is.
"We're not trying to convert V-8 customers," Luchansky says. "We're trying for converts that are coming out of either cars or sedans or another application that has a 2.0-liter turbo. If you have a turbo engine, you're going to want another turbo engine."
That's a shame, because the only thing stopping this 2.7 from supplanting the 5.3 entirely is the rusty old falsehood that V-8s are for trucks and four cylinders are for cars. That mountain of instantly available torque means that there's power everywhere. We've grown accustomed to responsive turbocharged engines, but this is something new, the instant rush of a small-displacement diesel in a gasoline powerplant.
Coupled with the eight-speed automatic, the Silverado turbo is properly quick, getting to 60 mph in 6.8 seconds. That's partly thanks to the fact that the new Silverado is much lighter than the outgoing model. Compared to a similarly equipped truck with the old 4.3-liter V-8, the 2019 pickup weighs 380 pounds less. The smaller engine makes up 80 of those.
We spent a morning chasing the hills around Phoenix in a four-wheel drive, double-cab Silverado LT that rang in at $44,900. Climbing the 3,500 feet of elevation from Scottsdale to the Tonto National Forest, the 2.7 simply dug in, parked itself at 2,000 rpm and tractored up the grades with zero drama. As we've come to expect from GM's cylinder deactivation, the system is seamless, all but imperceptible. From behind the wheel, there is no way we would have guessed that the engine under the hood was a four-cylinder, a shock given that for all its weight savings, the truck still weighs in at 4,693 pounds, unladen.
And as surprising as that is for a small-displacement engine in a massive pickup, we were more impressed with the way the Silverado drives. This is effectively a front mid-engine vehicle, with the engine's crank pulley sitting on the front axle line. It's no sports car, but it drives far better than a four-wheel drive pickup has any right to. Everything—steering, cornering, and braking—is a mile ahead of the old machine.
Nor does the four-cylinder require any great sacrifice in capability. GM hasn't released official payload or towing capacities, but the company estimates the 2.7-liter-equipped Silverado will be able to pull between 6,700 and 7,000 pounds. Likewise, GM hasn't released official EPA fuel economy estimates. We saw between 20 and 26.5 mpg indicated in mixed driving during our time behind the wheel. It's internally estimating 20/23 mpg city/highway.
It's a rare thing for a vehicle to so thoroughly exceed our expectations, but that's what the 2019 Silverado and its new 2.7-liter engine has managed to do. It's more truck than most half-ton pickup buyers will ever need or use: efficient, powerful, and quiet, all from a turbocharged four-cylinder.
2019 Silverado 1500 LT Double Cab 4WD Specifications
|PRICE||$41,695/$44,900 (base/as tested)|
|ENGINE||2.7L turbo DOHC 16-valve I-4/310 hp @ 5,600 rpm, 348 lb-ft @ 1,500-4,000 rpm|
|LAYOUT||4-door, 5-passenger, front-engine, 4WD truck|
|EPA MILEAGE||20/23 mpg (city/hwy) (est)|
|L x W x H||231.7 x 81.2.X x 75.6 in|
|0-60 MPH||6.8 sec|